Fuel pump with accessible body



A. M. BABITCH FUEL PUMP WITH ACCESSIBLE BODY May 8, 1934.

Filed Sept. 10, 1928 grvuwntoz $415174);

/Z/m/mr Patented May 8, 1934 UNITED STATES PATE T OFFICE FUEL PUMP WITH ACCESSIBLE BODY Abraham M. Babitch, Flint, Mich,

Application September 10, 1928, Serial No. 304,845 13 Claims. (Cl. 103-215) It is an object of this invention to so form amain structural element or body of a diaphragm fuel pump (said pump being preferably of substantially the same pressure-responsive and variable-stroke type as that described and claimed in my pending application S. N. 123,370, filed July 19, 1926) as to facilitate the assembly of interior parts,-said main structural element being downwardly terminated in an inclined plane and at such a level as to provide an opening through which the fingers of an operative may be introduced, for the insertion or removal of a pivot pin whereby a valve stem may be connected with a special actuating lever; and, in preferred embodiments of this invention, an additional structural element with the form of a bottom plate may not only be so formed as to close the relatively large opening thus provided into the interior. of the main casting but also adapted to receive one or more compression springs, as hereinafter described.

The diaphragms of diaphragm pumps being commonly provided with resilient means for imparting expulsion strokes thereto and with handling members such as so-called diaphragm stems for use in imparting intake strokes thereto from actuating elements such as rocker arms or levers movable by engine parts, it is an object of this invention, dispensing with any thrust-re- 39 fusing linkage between a diaphragm stem and cam-operated actuating'element, to so construct the latter that the length of stroke imparted to and through said stem may diminish with increase in the pressure built up above the pump diaphragm; and, for'the purpose here referred to, although said stem and said actuating element may be provided with compressionsprings seated in or upon the mentioned bottom closure element, said actuating element may comprise not only a uniform-stroke section but a variable-stroke section, these sections being preferably separately movable upon an identical pivot pin and provided with co-operating stop faces,-the periods of contact of said surfaces being dependent upon the level to which the pumping element may be depressed, and constant engagement. of the uniform -stroke section with a rotating cam, or the like, being assured by the pressure of one of said springs upona head or other part integrally or otherwise rigidly connectedwith said section.

Other features of this invention, including the provision of a construction favorable to the use of two practically equivalent, and therefore interchangeable, compression springs for purposes 55 above referred to (these springs being' preferably supported in parallel from the bottom closure plate, and at such a level above an opening into a crank case as to permit the return of any condensed water or other liquid to said case) and including also various details of construction designed to facilitate the installation of a pump or relating to a preferred type of sectional'lever which serves conditionally and variably to transmit motion from a rotating cam, or other cyclically moving engine part, to a handling member connected with a variably reciprocable pumping element, may be best appreciated from the following description of an illustrative embodiment thereof, taken in connection with the-appended claims and the accompanying drawing.

Fig. 1 may be referred to as a substantially median vertical section,-this view being taken in the plane indicated by the line 11 of Fig.2.

Fig. 2 is, for the most part, an elevational view, taken from the direction indicated by the arrow 5 2 of Fig. 1,parts immaterial to the present invention being shown as broken away and a bottom closure plate being omitted, together with parts carried thereby.

Fig. 3 is a sectional view, taken substantially as indicated by the broken line 3-3 of Fig. 1.

Referring to details of that embodiment of the present invention chosen for purposes of illustration, a main structural element or body casting 10 and a subsidiary structural element in the form of a cover casting 11 are shown as co-opcrating in the retention of a reciprocable pumping member in the form of a diaphragm 12; and the main casting 10 is shown as provided with a flange 13, suitable for use in securing the same opposite an opening 14 in, for example, the crank case of an engine 15,--including a cyclically movingpart such as an engine crank shaft or cam shaft 16 carrying a cam or eccentric 17. The diaphragm 12 is shown as secured to a handling member in the form of a diaphragm stem 18 by means comprising a nut 19 and suitable plates and washers; a transverse web is shown as so aperturedat 20 as to permit alimited play of the diaphragm stem during its reciprocation therein by means of a suitable actuating member; and the present invention should beunderstood to relate not only to the casting 10 and to a bottom closure element therefor, but to the specific character of a sectional actuating lever, serving for the conditional transmission of motion from the cam 17 to the diaphragm stem 18, and to features of special construction facilitating the assembly of the parts last referred to and invoiving the use of separate but identical or very gasket 24 is optionally interposed and means suchv as screws 25 may be employed to retain said plate.

The closure plate 23 may be provided with means such as hollow bosses or projections 26, 26', adapted to facilitate the positioning of separate but similar compression springs 27, 27'. These are shown as disposed in parallel and respectively provided with socket caps 28, 28' and as resiliently applying upward pressure respectively to the diaphragm stem 18 (conditionally to effect expulsion strokes of the reciprocatory' pumping member 12) and to a head 29, shown as integral with a motion-receiving section 30 of a sectional actuating lever above referred to. Not only the motion-receiving section 30 of the mentioned actuating lever but a motion-imparting section thereof, shown as comprising substantially parallel side plates 31, 31', may be pivoted to the main casting l0,-as by means of a single pivot pin 32; the opposite ends of the side plates 31, 31' may be pivotally or otherwise operatively connected with the diaphragm stem 18, or its equivalent, by means such as an additional pin 33; and the respective lever sections referred to may be provided with 'interengaging stop elements such as opposable faces 34, 35, so disposed as to impart a full stroke to the diaphragm 12, or an equivalent pumping element, only when the pressure within a pump chamber 36, shown as provided within the casting 11, is such as to permit a full stroke of said pumping element, under the pressure applied by the calibrated spring 27 or its equivalent.

That is to say, so long as the pressure within the chamber 36 remains low, the rocking of the arm or lever section between positionssuch as are respectively shown in full lines and in dotted lines in Fig. 1 may result in a corresponding reciprocation of the diaphragm 12; but whenever the pressure within the chamber 36 is such as to hold said diaphragm depressed, thereby separating the stop faces 34, 35 during a part or thewhole of a reciprocation of the arm 30, the continued rocking of the motion-receiving arm 30 may have no corresponding effect upon the motion-imparting arm comprising plates 31, 31'. It will be seen that the positions of the described movable members are favorable to automatic lubrication thereof; and, since arm 30 is held constantly in contact with cam 1'7, and the faces 34, 35. become parallel only at the moment of their engagement, a film of oil accumulating therebetween may be relied upon to prevent con-- tact noises. The length of stroke thus imparted is naturally dependent upon the pressure within chamber 36; and may automatically vary, in response to variations in fuel consumption, between a full stroke and no stroke.

Not only the described, configurations of the main casting 10 and the bottom closure'casting but the employment of substantially identical springs ,27, 27 (both being easily positioned uponthe assembly or reassembly of the described parts; drainage of condensed water or other liquid may .be effected through an opening 3'7, below lever opening 38, and, as a further aid in assembly and installation, the mentioned head 29, shown as integral with the motion-receiving arm 30, may upwardly terminate in a rounded projection 39, capable of momentarily engaging the transverse web 40 to hold the arm 30 in some upwardlyextending position during the positioning of a pump relatively to an engine casing.

Although the foregoing description includes but one embodiment of the present invention, it will be obvious not only that various features thereof might be independently employed but also that numerous modifications may be devised, without involving the slightest departure from the spirit and scope of the invention, as the latter is indicated above and in the following claims.

I claim:

1. In a fuel pump comprising a pump chamber element and a reciprocable pumping member provided with a handling member having a sectional lever member operatively connected therewith: a .hollow main structural element adapted to receive said members and downwardly terminating in an inclined plane at such a level as to provide an opening which facilitates manual assembly and interconnection of mentioned members-saidopening being provided with a bottom closure plate having a co-operating surface and provided with means for the support of the plurality of compression springs; and springs thereon, upwardly acting upon mentioned members.

2. In a fuel pump comprising a fuel pump chamber element and a reciprocable pumping member provided with a handling member having an actuating lever member operatively connected therewith: a hollow main structural element adapted to support said members and provided with means for its support from an engine body; a bottom plate which co-operates with said structural element, engaging the same at an angle favorable to access to said main element and shaped to carry a spring; and a compression spring seated therein and upwardly acting upon at least one of said members.

3. In a fuel pump comprising a fuel pump chamber element and a reciprocable pumping member provided with a handling member having a sectional actuating lever member operatively connected therewith: a hollow main structural element adapted to support said members and provided with means for its support from an engine body; a bottom plate structural element which co-operates with said main structural element and has means to carry springs; and a plurality of compression springs carried thereby, and respectively acting upon said lever and said stem, conditionally to advance the same even during parts of return strokes of said lever, at,

ing closure means in the form of a plate diagonally secured to said hollow elements,-one of 5 said means providing means for a substantially complete drainage of said body away from said springs.

5. In a fuel pump comprising a pump chamber element and a reciprocable pumping member provided with a handlingmember having a sectional actuating lever member operatively connected therewith: a hollow main structural element adapted to support said members and provided with means for its support from an engine body; an additional structural element to carry springs; and a plurality of compression springs carried thereby and respectively acting upon said lever and said stem, conditionally to advance the same even during parts of return strokes of said lever, said springs being interchangeable.

, 6. In a fuel pump comprising a pump chamber element and a reciprocable pumping member provided with a handling member having a sectional actuating lever member operatively connected therewith: means for supporting springs; a main structural element housing said members; and interchangeable compression springs secured in parallel therebelow' and acting respectively to advance said handling member in order to produce variable expulsion strokes of said pumping member, and to hold a section of said lever member in constant engagement with a cam.

'7. For use in a fuel pump comprising a pump chamber element and a reciprocable pumping member provided with a handling member having a sectional actuating lever operatively connected therewith, a variable-stroke sectional lever comprising: a motion-receiving section and a motion-imparting section which are respectively provided with opposable stop faces, said motion-receiving section comprising a head which is adapted to so receive resilient pressure as to hold said section constantly in engagement with a cam.

8. In a fuel pump comprising a pump chamber element and a reciprocable pumping member provided with a handling member having a sectional actuating lever operatively connected therewith: a sectional lever comprising a motionreceiving section and a motion-imparting section which are respectively provided with opposable stop faces, said motion-receiving section being provided with a part which is adapted to limit the movement of said section during assembly of said pump. I

9. For use in a fuel pump of the general character described, actuating means in the form of a sectional lever suitable for interposition between a cyclically moving part and a valve stem, said lever comprisingz-a motion-receiving section including a cam-engaging arm provided with a head adapted to receive constantly such, pressure as to hold said arm in engagement with said part; and a motion-imparting section comprising separate plates between which said head is disposed, said sections being provided with opposable stop faces.

10. A fuel pump comprising: structural elements including a pump chamber element; a pumping member reciprocable relatively thereto; a handling member secured to said pum ing member; a uniform-throw lever member; a pivotally connected link member extending between said handling member and said lever member; and means for so limiting the angular movement between said link and said lever member as conditionally to constitute the former an inward extension of the latter.

11. A fuel pump comprising: structural elements including a pump chamber element; a pumping member reciprocable relatively thereto; a handling member secured to said pumping member; a uniform-throw lever member; a link her and said lever member; and means for so .limiting the angular movement between said link and said lever member as conditionally to constitute the former an inward extension of the latter,-said pumping member being provided with means rendering advance thereof dependent upon pressure conditions thereabove, and said angular movement being increased as said pressureis increased.

12. In a pumping apparatus for the purpose indicated, a casing having a pumping chamber and a pumping member operating therein, camactuated lever means for operating the pumping member, said lever means comprising two levers having a common fulcrum and having cooperating stops for causing them to move together in one direction about their fulcrum, the first lever being associated with the cam for positive actuation in the active phase of the cam, a spring reacting on said first lever to cause it to follow the cam in the idle phase of the cam cycle, said spring being mounted in a position between the fulcrum for the levers and the pumping member, and a second spring reacting on the pumping member in the direction of its fuel impelling stroke, and on the second lever in the direction for holding the cooperating stops of the two levers in engagement.

13. In a pumping apparatus for the purpose indicated, a casing having a pumping chamber and a pumping member operating therein, camactuated lever means for operating the pumping member comprising two levers having a common fulcrum and cooperating stops for causing them to move together in one direction about their fulcrums, one of said levers being extended for positive actuation in the active phase of the cam, and the other being operatively connected with the pumping member, spring means for holding said levers with their stops. in engagement for such movement together and other spring means reacting on the first lever for causing it to follow a position between the fulcrum for the levers and said pumping member.

ABRAHAM M. BABITCH.

Bit" 

